1. General Results, most used to calculate the result A name "mqtt.denetmen.app" is subdomain, public suffix is ".app", top-level-domain is ".app", top-level-domain-type is "generic", tld-manager is "Charleston Road Registry Inc.", num .app-domains preloaded: 42 (complete: 175327) A Good: All ip addresses are public addresses Warning: Only one ip address found: mqtt.denetmen.app has only one ip address. Warning: Only one ip address found: www.mqtt.denetmen.app has only one ip address. Warning: No ipv6 address found. Ipv6 is the future with a lot of new features. So every domain name should have an ipv6 address. See https://en.wikipedia.org/wiki/IPv6: mqtt.denetmen.app has no ipv6 address. Warning: No ipv6 address found. Ipv6 is the future with a lot of new features. So every domain name should have an ipv6 address. See https://en.wikipedia.org/wiki/IPv6: www.mqtt.denetmen.app has no ipv6 address. A Good: No asked Authoritative Name Server had a timeout A Good: No cookie sent via http. A Excellent: Main Domain is in the Google-Preload-List A Excellent: Main Domain is in the Mozilla/Firefox-Preload-List A HSTS-Preload-Status: Preloaded. Check https://hstspreload.org/ to learn some basics about the Google-Preload-List. A Good: Some urls with http status 200/404 have a complete Content-Type header (MediaType / MediaSubType + correct charset):0 complete Content-Type - header (7 urls) http://mqtt.denetmen.app/ 185.210.95.153 Url with incomplete Content-Type - header - missing charset http://www.mqtt.denetmen.app/ 185.210.95.153 Url with incomplete Content-Type - header - missing charset https://mqtt.denetmen.app/ 185.210.95.153 Url with incomplete Content-Type - header - missing charset https://www.mqtt.denetmen.app/ 185.210.95.153 Url with incomplete Content-Type - header - missing charset http://mqtt.denetmen.app/.well-known/acme-challenge/check-your-website-dot-server-daten-dot-de 185.210.95.153 Url with incomplete Content-Type - header - missing charset http://www.mqtt.denetmen.app/.well-known/acme-challenge/check-your-website-dot-server-daten-dot-de 185.210.95.153 Url with incomplete Content-Type - header - missing charset https://185.210.95.153/ 185.210.95.153 Url with incomplete Content-Type - header - missing charset B https://mqtt.denetmen.app/ 185.210.95.153 Missing HSTS-Header B https://www.mqtt.denetmen.app/ 185.210.95.153 Missing HSTS-Header C Error - no preferred version www or non-www. Select one version as preferred version, then add a redirect https + not-preferred version to https + preferred version. Perhaps in your port 443 vHost something like "RewriteEngine on" + "RewriteCond %{SERVER_NAME} = example.com" + "ReWriteRule ^ https://www.example.com%{REQUEST_URI} [END,QSA,R=permanent]" (three rows, without the "). That should create a redirect https + example.com ⇒ https + www.example.com. Or switch both values to use the non-www version as your preferred version. C Error - more then one version with Http-Status 200. After all redirects, all users (and search engines) should see the same https url: Non-www or www, but not both with http status 200. H Fatal error: http result with http-status 200, no encryption. Add a redirect http ⇒ https, so every connection is secure. Perhaps in your port 80 vHost something like "RewriteEngine on" + "RewriteRule ^ https://%{SERVER_NAME}%{REQUEST_URI} [END,QSA,R=permanent]" (two rows, without the "). Don't add this in your port 443 vHost, that would create a loop. N https://185.210.95.153/ 185.210.95.153 Error - Certificate isn't trusted, RemoteCertificateNameMismatch N mqtt.denetmen.app:465 Error - Certificate isn't trusted, RemoteCertificateNameMismatch N mqtt.denetmen.app:993 Error - Certificate isn't trusted, RemoteCertificateNameMismatch N mqtt.denetmen.app:995 Error - Certificate isn't trusted, RemoteCertificateNameMismatch N mqtt.denetmen.app:8443 Error - Certificate isn't trusted, RemoteCertificateNameMismatch N www.mqtt.denetmen.app:465 Error - Certificate isn't trusted, RemoteCertificateNameMismatch N www.mqtt.denetmen.app:993 Error - Certificate isn't trusted, RemoteCertificateNameMismatch N www.mqtt.denetmen.app:995 Error - Certificate isn't trusted, RemoteCertificateNameMismatch N www.mqtt.denetmen.app:8443 Error - Certificate isn't trusted, RemoteCertificateNameMismatch N 185.210.95.153:465 Error - Certificate isn't trusted, RemoteCertificateNameMismatch N 185.210.95.153:993 Error - Certificate isn't trusted, RemoteCertificateNameMismatch N 185.210.95.153:995 Error - Certificate isn't trusted, RemoteCertificateNameMismatch N 185.210.95.153:8443 Error - Certificate isn't trusted, RemoteCertificateNameMismatch Info: Checking all ip addresses of that domain without sending the hostname only one certificate found. Checking all ip addresses and sending the hostname only one certificate found. Both certificates are different. So that domain requires Server Name Indication (SNI), so the server is able to select the correct certificate.: Domain mqtt.denetmen.app, 1 ip addresses. Info: Checking all ip addresses of that domain without sending the hostname only one certificate found. Checking all ip addresses and sending the hostname only one certificate found. Both certificates are different. So that domain requires Server Name Indication (SNI), so the server is able to select the correct certificate.: Domain www.mqtt.denetmen.app, 1 ip addresses. 2. Header-Checks (alpha, started 2022-10-23, may be buggy / incomplete) 3. DNS- and NameServer - Checks A Info:: 7 Root-climbing DNS Queries required to find all IPv4- and IPv6-Addresses of 2 Name Servers. A Info:: 7 Queries complete, 3 with IPv6, 4 with IPv4. Warning: Only some DNS Queries done via ipv6. IPv6 is the future, so the name servers of your name servers should have ipv6 addresses. Ok (4 - 8):: An average of 3.5 queries per domain name server required to find all ip addresses of all name servers. A Info:: 2 different Name Servers found: ns1.mqtt.denetmen.app, ns2.mqtt.denetmen.app, 2 Name Servers included in Delegation: ns1.mqtt.denetmen.app, ns2.mqtt.denetmen.app, 2 Name Servers included in 1 Zone definitions: ns1.mqtt.denetmen.app, ns2.mqtt.denetmen.app, 1 Name Servers listed in SOA.Primary: ns2.mqtt.denetmen.app. A Good: Only one SOA.Primary Name Server found.: ns2.mqtt.denetmen.app. A Good: SOA.Primary Name Server included in the delegation set.: ns2.mqtt.denetmen.app. A Good: Consistency between delegation and zone. The set of NS records served by the authoritative name servers must match those proposed for the delegation in the parent zone. Ordered list of name servers: ns1.mqtt.denetmen.app, ns2.mqtt.denetmen.app A Good: All Name Server Domain Names have a Public Suffix. A Good: All Name Server Domain Names ending with a Public Suffix have minimal one IPv4- or IPv6 address. A Good: All Name Server ip addresses are public. A Good: Minimal 2 different name servers (public suffix and public ip address) found: 2 different Name Servers found Warning: No Name Server IPv6 address found. IPv6 is the future, so your name servers should be visible via IPv6.: 2 different Name Servers found Warning: All Name Servers have the same Top Level Domain / Public Suffix. If there is a problem with that Top Level Domain, your domain may be affected. Better: Use Name Servers with different top level domains.: 2 Name Servers, 1 Top Level Domain: app Warning: All Name Servers have the same domain name. If there is a problem with that domain name (or with the name servers of that domain name), your domain may be affected. Better: Use Name Servers with different domain names / different top level domains.: Only one domain name used: denetmen.app Warning: All Name Servers from the same Country / IP location.: 2 Name Servers, 1 Countries: TR A Info: Ipv4-Subnet-list: 2 Name Servers, 1 different subnets (first Byte): 185., 1 different subnets (first two Bytes): 185.210., 1 different subnets (first three Bytes): 185.210.95. X Fatal: All Name Server IPv4 addresses from the same subnet. Check https://www.iana.org/help/nameserver-requirements to learn some basics about name server configurations. If you manage these name servers, fix it. If it's your provider, change your provider.: X Fatal: Only one Name Server IPv4 address found. Check https://www.iana.org/help/nameserver-requirements to learn some basics about name server configurations. If you manage these name servers, fix it. If it's your provider, change your provider. A Good: Nameserver supports TCP connections: 2 good Nameserver A Good: Nameserver supports Echo Capitalization: 2 good Nameserver A Good: Nameserver supports EDNS with max. 512 Byte Udp payload, message is smaller: 2 good Nameserver A Good: Nameserver has passed 10 EDNS-Checks (OP100, FLAGS, V1, V1OP100, V1FLAGS, DNSSEC, V1DNSSEC, NSID, COOKIE, CLIENTSUBNET): 2 good Nameserver A Good: All SOA have the same Serial Number Warning: No CAA entry with issue/issuewild found, every CAA can create a certificate. Read https://en.wikipedia.org/wiki/DNS_Certification_Authority_Authorization to learn some basics about the idea of CAA. Your name server must support such an entry. Not all dns providers support CAA entries. 4. Content- and Performance-critical Checks A Good: All checks /.well-known/acme-challenge/random-filename without redirects answer with the expected http status 404 - Not Found. Creating a Letsencrypt certificate via http-01 challenge should work. If it doesn't work: Check your vHost configuration (apachectl -S, httpd -S, nginx -T). Every combination of port and ServerName / ServerAlias (Apache) or Server (Nginx) must be unique. Merge duplicated entries in one vHost. If you use an IIS, extensionless files must be allowed in the /.well-known/acme-challenge subdirectory. Create a web.config in that directory. Content: <configuration><system.webServer><staticContent><mimeMap fileExtension="." mimeType="text/plain" /></staticContent></system.webServer></configuration>. If you have a redirect http ⇒ https, that's ok, Letsencrypt follows such redirects to port 80 / 443 (same or other server). There must be a certificate. But the certificate may be expired, self signed or with a not matching domain name. Checking the validation file Letsencrypt ignores such certificate errors. Trouble creating a certificate? Use https://community.letsencrypt.org/ to ask. https://mqtt.denetmen.app/ 185.210.95.153 Warning: https result with status 200 and size greater then 1024 Bytes without GZip found. Add GZip support so the html content is compressed. https://www.mqtt.denetmen.app/ 185.210.95.153 Warning: https result with status 200 and size greater then 1024 Bytes without GZip found. Add GZip support so the html content is compressed. https://185.210.95.153/ 185.210.95.153 Warning: https result with status 200 and size greater then 1024 Bytes without GZip found. Add GZip support so the html content is compressed. https://mqtt.denetmen.app/ 185.210.95.153 Warning: Https + http status 200 + Inline CSS / JavaScript found. Don't use inline CSS / JavaScript. These are compiled and re-used ressources, save these with a long Cache-Control max-age - header. https://www.mqtt.denetmen.app/ 185.210.95.153 Warning: Https + http status 200 + Inline CSS / JavaScript found. Don't use inline CSS / JavaScript. These are compiled and re-used ressources, save these with a long Cache-Control max-age - header. https://185.210.95.153/ 185.210.95.153 Warning: Https + http status 200 + Inline CSS / JavaScript found. Don't use inline CSS / JavaScript. These are compiled and re-used ressources, save these with a long Cache-Control max-age - header. https://mqtt.denetmen.app/ 185.210.95.153 Warning: Https result with status 200 found, Html-Content is too big. Should be max. 110 %. May contain inline CSS / JavaScript, too much comments or white space. Re-used ressources - create files with a long Cache-Control max-age header. Remove comments and white space. https://www.mqtt.denetmen.app/ 185.210.95.153 Warning: Https result with status 200 found, Html-Content is too big. Should be max. 110 %. May contain inline CSS / JavaScript, too much comments or white space. Re-used ressources - create files with a long Cache-Control max-age header. Remove comments and white space. https://185.210.95.153/ 185.210.95.153 Warning: Https result with status 200 found, Html-Content is too big. Should be max. 110 %. May contain inline CSS / JavaScript, too much comments or white space. Re-used ressources - create files with a long Cache-Control max-age header. Remove comments and white space. https://mqtt.denetmen.app/ 185.210.95.153 Warning: Https connections (Standard Port 443) found without support of the http/2 protocol via ALPN. Http/2 is the new Http-Version (old: http 1.1) with some important new features. Update your server software so http/2 is available. Only one TCP-connection per Server (that's a performance boost), Header-Compression and Server Pushs are available. Domain Sharding and Inline-CSS/Javascript shouldn't used with http/2. https://www.mqtt.denetmen.app/ 185.210.95.153 Warning: Https connections (Standard Port 443) found without support of the http/2 protocol via ALPN. Http/2 is the new Http-Version (old: http 1.1) with some important new features. Update your server software so http/2 is available. Only one TCP-connection per Server (that's a performance boost), Header-Compression and Server Pushs are available. Domain Sharding and Inline-CSS/Javascript shouldn't used with http/2. https://185.210.95.153/ 185.210.95.153 Warning: Https connections (Standard Port 443) found without support of the http/2 protocol via ALPN. Http/2 is the new Http-Version (old: http 1.1) with some important new features. Update your server software so http/2 is available. Only one TCP-connection per Server (that's a performance boost), Header-Compression and Server Pushs are available. Domain Sharding and Inline-CSS/Javascript shouldn't used with http/2. https://mqtt.denetmen.app/ 185.210.95.153 Critical: Some script Elements (type text/javascript) with a src-Attribute don't have a defer / async - Attribute. Loading and executing these JavaScripts blocks parsing and rendering the Html-Output. That's bad if your site is large or the connection is slow / mobile usage. Use "async" if the js file has only functions (so nothing is executed after parsing the file) or is independend. Use "defer" if the order of the scripts is important. All "defer" scripts are executed before the DOMContentLoaded event is fired. Check https://developer.mozilla.org/en-US/docs/Web/HTML/Element/script to see some details.: 4 script elements without defer/async. https://www.mqtt.denetmen.app/ 185.210.95.153 Critical: Some script Elements (type text/javascript) with a src-Attribute don't have a defer / async - Attribute. Loading and executing these JavaScripts blocks parsing and rendering the Html-Output. That's bad if your site is large or the connection is slow / mobile usage. Use "async" if the js file has only functions (so nothing is executed after parsing the file) or is independend. Use "defer" if the order of the scripts is important. All "defer" scripts are executed before the DOMContentLoaded event is fired. Check https://developer.mozilla.org/en-US/docs/Web/HTML/Element/script to see some details.: 4 script elements without defer/async. https://185.210.95.153/ 185.210.95.153 Critical: Some script Elements (type text/javascript) with a src-Attribute don't have a defer / async - Attribute. Loading and executing these JavaScripts blocks parsing and rendering the Html-Output. That's bad if your site is large or the connection is slow / mobile usage. Use "async" if the js file has only functions (so nothing is executed after parsing the file) or is independend. Use "defer" if the order of the scripts is important. All "defer" scripts are executed before the DOMContentLoaded event is fired. Check https://developer.mozilla.org/en-US/docs/Web/HTML/Element/script to see some details.: 1 script elements without defer/async. Warning: CSS / JavaScript found without GZip support. Send these ressources with GZip. 16 external CSS / JavaScript files without GZip found - 0 with GZip, 16 complete Warning: CSS / JavaScript files with a missing or too short Cache-Control header found. Browsers should cache and re-use these files. 18 external CSS / JavaScript files without Cache-Control-Header, 0 with Cache-Control, but no max-age, 0 with Cache-Control max-age too short (minimum 7 days), 0 with Cache-Control long enough, 18 complete. Warning: Images with a missing or too short Cache-Control header found. Browsers should cache and re-use these files. 1 image files without Cache-Control-Header, 0 with Cache-Control, but no max-age, 0 with Cache-Control max-age too short (minimum 7 days), 0 with Cache-Control long enough, 1 complete. A Good: Some checked attribute values are enclosed in quotation marks (" or ').: 63 Html-Elements checked, 35 without problems. I Wrong: Attribute values found, not enclosed in quotation marks (" or ').: 28 Html-Elements with attributes and missing enclosed quotation marks found. 36 wrong attributes. A Good: All img-elements have a valid alt-attribute.: 1 img-elements found. A Good: Domainname is not on the "Specially Designated Nationals And Blocked Persons List" (SDN). That's an US-list of individuals and companies owned or controlled by, or acting for or on behalf of, targeted countries. It also lists individuals, groups, and entities, such as terrorists and narcotics traffickers designated under programs that are not country-specific. Collectively, such individuals and companies are called "Specially Designated Nationals" or "SDNs." Their assets are blocked and U.S. persons are generally prohibited from dealing with them. So if a domain name is on that list, it's impossible to create a Letsencrypt certificate with that domain name. Check the list manual - https://www.treasury.gov/resource-center/sanctions/sdn-list/pages/default.aspx A Duration: 155010 milliseconds, 155.010 seconds